v4.19.13 snapshot.
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
new file mode 100644
index 0000000..79debfc
--- /dev/null
+++ b/fs/crypto/fscrypt_private.h
@@ -0,0 +1,120 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * fscrypt_private.h
+ *
+ * Copyright (C) 2015, Google, Inc.
+ *
+ * This contains encryption key functions.
+ *
+ * Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
+ */
+
+#ifndef _FSCRYPT_PRIVATE_H
+#define _FSCRYPT_PRIVATE_H
+
+#define __FS_HAS_ENCRYPTION 1
+#include <linux/fscrypt.h>
+#include <crypto/hash.h>
+
+/* Encryption parameters */
+#define FS_IV_SIZE 16
+#define FS_KEY_DERIVATION_NONCE_SIZE 16
+
+/**
+ * Encryption context for inode
+ *
+ * Protector format:
+ * 1 byte: Protector format (1 = this version)
+ * 1 byte: File contents encryption mode
+ * 1 byte: File names encryption mode
+ * 1 byte: Flags
+ * 8 bytes: Master Key descriptor
+ * 16 bytes: Encryption Key derivation nonce
+ */
+struct fscrypt_context {
+ u8 format;
+ u8 contents_encryption_mode;
+ u8 filenames_encryption_mode;
+ u8 flags;
+ u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
+ u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE];
+} __packed;
+
+#define FS_ENCRYPTION_CONTEXT_FORMAT_V1 1
+
+/**
+ * For encrypted symlinks, the ciphertext length is stored at the beginning
+ * of the string in little-endian format.
+ */
+struct fscrypt_symlink_data {
+ __le16 len;
+ char encrypted_path[1];
+} __packed;
+
+/*
+ * A pointer to this structure is stored in the file system's in-core
+ * representation of an inode.
+ */
+struct fscrypt_info {
+ u8 ci_data_mode;
+ u8 ci_filename_mode;
+ u8 ci_flags;
+ struct crypto_skcipher *ci_ctfm;
+ struct crypto_cipher *ci_essiv_tfm;
+ u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE];
+};
+
+typedef enum {
+ FS_DECRYPT = 0,
+ FS_ENCRYPT,
+} fscrypt_direction_t;
+
+#define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
+#define FS_CTX_HAS_BOUNCE_BUFFER_FL 0x00000002
+
+static inline bool fscrypt_valid_enc_modes(u32 contents_mode,
+ u32 filenames_mode)
+{
+ if (contents_mode == FS_ENCRYPTION_MODE_AES_128_CBC &&
+ filenames_mode == FS_ENCRYPTION_MODE_AES_128_CTS)
+ return true;
+
+ if (contents_mode == FS_ENCRYPTION_MODE_AES_256_XTS &&
+ filenames_mode == FS_ENCRYPTION_MODE_AES_256_CTS)
+ return true;
+
+ return false;
+}
+
+/* crypto.c */
+extern struct kmem_cache *fscrypt_info_cachep;
+extern int fscrypt_initialize(unsigned int cop_flags);
+extern int fscrypt_do_page_crypto(const struct inode *inode,
+ fscrypt_direction_t rw, u64 lblk_num,
+ struct page *src_page,
+ struct page *dest_page,
+ unsigned int len, unsigned int offs,
+ gfp_t gfp_flags);
+extern struct page *fscrypt_alloc_bounce_page(struct fscrypt_ctx *ctx,
+ gfp_t gfp_flags);
+extern const struct dentry_operations fscrypt_d_ops;
+
+extern void __printf(3, 4) __cold
+fscrypt_msg(struct super_block *sb, const char *level, const char *fmt, ...);
+
+#define fscrypt_warn(sb, fmt, ...) \
+ fscrypt_msg(sb, KERN_WARNING, fmt, ##__VA_ARGS__)
+#define fscrypt_err(sb, fmt, ...) \
+ fscrypt_msg(sb, KERN_ERR, fmt, ##__VA_ARGS__)
+
+/* fname.c */
+extern int fname_encrypt(struct inode *inode, const struct qstr *iname,
+ u8 *out, unsigned int olen);
+extern bool fscrypt_fname_encrypted_size(const struct inode *inode,
+ u32 orig_len, u32 max_len,
+ u32 *encrypted_len_ret);
+
+/* keyinfo.c */
+extern void __exit fscrypt_essiv_cleanup(void);
+
+#endif /* _FSCRYPT_PRIVATE_H */